But |cat alive> + |cat dead> is a natural basis because that’s the basis in which the interaction occurs. No mystery there; you can’t perceive something without interacting with it, and an interaction is likely to have some sort of privileged basis.
Regarding basis as an observers own choice of “co-ordinate grid”, and regarding observing (or instrument) as having a natural basis , is a simple and powerful theory of basis. Since an observer’s natural basis is the one that minimises superpositions, the fact that observers make quasi-classical observations drops out naturally, without any cosmological assumptions. But, since there is no longer a need for a global and objective basis, a basis that is a feature of the universe, there is no longer a possibility of many worlds as an objective feature of the universe: since an objective basis is needed to objectively define a division into worlds, there such a division is no longer possible, and splitting is an observer-dependent phenomenon.
We’d still expect strongly interacting systems e.g. the earth (and really, the solar system?) to have an objective splitting. But it seems correct to say that I basically don’t know how far that extends.
Why? If you could prove that large environments must cause decoherence into n>1 branches you would have solved the measurement problem as it is currently understood.
This is just chaos theory, isn’t it? If one person sees that Schrodinger’s cat is dead, then they’re going to change their future behavior, which changes the behavior of everyone they interact with, and this then butterflies up to entangle the entire earth in the same superposition.
You’re saying that if you have decoherent splitting of an observer, that leads to more decoherent splitting. But where does the initial decoherent splitting come from?
The observer is highly sensitive to differences along a specific basis, and therefore changes a lot in response to that basis. Due to chaos, this then leads to everything else on earth getting entangled with the observer in that same basis, implying earth-wide decoherence.
What does highly sensitive mean? In classical physics, an observer can produce an energy output much greater than the energy input of the observation. ,but no splitting is implied. In bare Everettian theory, an observer becomes entangled with the coherent superposition they are observing, and goes into a coherent superposition themself ..so no decoherentsplitting is implied. You still haven’t said where and the initial decoherent splitting occurs.
But |cat alive> + |cat dead> is a natural basis because that’s the basis in which the interaction occurs. No mystery there; you can’t perceive something without interacting with it, and an interaction is likely to have some sort of privileged basis.
Regarding basis as an observers own choice of “co-ordinate grid”, and regarding observing (or instrument) as having a natural basis , is a simple and powerful theory of basis. Since an observer’s natural basis is the one that minimises superpositions, the fact that observers make quasi-classical observations drops out naturally, without any cosmological assumptions. But, since there is no longer a need for a global and objective basis, a basis that is a feature of the universe, there is no longer a possibility of many worlds as an objective feature of the universe: since an objective basis is needed to objectively define a division into worlds, there such a division is no longer possible, and splitting is an observer-dependent phenomenon.
We’d still expect strongly interacting systems e.g. the earth (and really, the solar system?) to have an objective splitting. But it seems correct to say that I basically don’t know how far that extends.
Why? If you could prove that large environments must cause decoherence into n>1 branches you would have solved the measurement problem as it is currently understood.
This is just chaos theory, isn’t it? If one person sees that Schrodinger’s cat is dead, then they’re going to change their future behavior, which changes the behavior of everyone they interact with, and this then butterflies up to entangle the entire earth in the same superposition.
You’re saying that if you have decoherent splitting of an observer, that leads to more decoherent splitting. But where does the initial decoherent splitting come from?
The observer is highly sensitive to differences along a specific basis, and therefore changes a lot in response to that basis. Due to chaos, this then leads to everything else on earth getting entangled with the observer in that same basis, implying earth-wide decoherence.
What does highly sensitive mean? In classical physics, an observer can produce an energy output much greater than the energy input of the observation. ,but no splitting is implied. In bare Everettian theory, an observer becomes entangled with the coherent superposition they are observing, and goes into a coherent superposition themself ..so no decoherentsplitting is implied. You still haven’t said where and the initial decoherent splitting occurs.
Hi? Edit: the parent comment originally just had a single word saying “Test”